+91-87964 74404
FlagBACK
Question icon
Grade 11Trigonometry

If Cosa=kcosb then show that tan(a+b/2)=(1-k)/(1+k)cot(a-b/2)

Profile image of Ritusree Biswas
8 Years agoGrade 11
Answers icon

1 Answer

Profile image of sonika p
8 Years ago
cosa/cosb = k
(cos b – cos a)/(cos b + cos a)  = (1-k) / (1+k)
[sin ((a-b)/2)sin((a+b)/2)]/ [cos ((a-b)/2)cos((a+b)/2)] = (1-k) / (1+k)
[tan ((a-b)/2)tan((a+b)/2)] = (1-k) / (1+k)
tan((a+b)/2) = [(1-k) / (1+k)] cot ((a-b)/2)

Other Related Questions on trigonometry

question mark
In ABC, if cot A+cot B+cot C = cosecA cosecB cosecC, then prove that ABC is right angle triangle.
trigonometry
1 Answer Available

Last Activity: 3 Years ago

question mark
  • Find the general solution of equation tan3∂=cot2∂
For all angles between -720 and +720
trigonometry
1 Answer Available

Last Activity: 4 Years ago

question mark
To prove : Cosec(45 degree - A)Cosec(45 degree + A) = 2SecA
trigonometry
1 Answer Available

Last Activity: 4 Years ago

question mark
Derive a formula for the area of the triangle, given b, A, B, and C. That is, derive the formula: (b^2sinAsinC)/(2sinB)
trigonometry
1 Answer Available

Last Activity: 4 Years ago

question mark
WHAT IS THE LIMIT WHEN X TOWARDS TO 0 OF sin6x/5x ? lim𝑥→0 𝑠𝑖𝑛6𝑥/5𝑥 
trigonometry
1 Answer Available

Last Activity: 4 Years ago